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<title>Struct template vararg</title>
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<h2><span class="refentrytitle">Struct template vararg</span></h2>
<p>boost::proto::vararg — For matching a Grammar to a variable number of sub-expressions.</p>
</div>
<h2 class="refsynopsisdiv-title">Synopsis</h2>
<div class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: &lt;<a class="link" href="../../proto/reference.html#header.boost.proto.matches_hpp" title="Header &lt;boost/proto/matches.hpp&gt;">boost/proto/matches.hpp</a>&gt;

</span><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> Grammar<span class="special">&gt;</span> 
<span class="keyword">struct</span> <a class="link" href="vararg.html" title="Struct template vararg">vararg</a> <span class="special">{</span>
<span class="special">}</span><span class="special">;</span></pre></div>
<div class="refsect1">
<a name="id-1.3.32.5.34.12.4"></a><h2>Description</h2>
<p>
            An expression type <code class="computeroutput"><a class="link" href="basic_expr.html" title="Struct template basic_expr">proto::basic_expr</a>&lt;AT,
            <a class="link" href="listN.html" title="Struct template listN">proto::listN</a>&lt;A<sub>0</sub>,...A<sub>n</sub>,U<sub>0</sub>,...U<sub>m</sub>&gt; &gt;</code>
            matches a grammar <code class="computeroutput"><a class="link" href="basic_expr.html" title="Struct template basic_expr">proto::basic_expr</a>&lt;BT,
            <a class="link" href="listN.html" title="Struct template listN">proto::listM</a>&lt;B<sub>0</sub>,...B<sub>n</sub>,proto::vararg&lt;V&gt; &gt; &gt;</code>
            if <code class="computeroutput">BT</code> is <code class="computeroutput"><a class="link" href="_.html" title="Struct _">proto::_</a></code>
            or <code class="computeroutput">AT</code>, and if
            <code class="computeroutput">A<sub>x</sub></code> matches
            <code class="computeroutput">B<sub>x</sub></code>
            for each <code class="computeroutput">x</code> in <code class="computeroutput">[0,n]</code>
            and if <code class="computeroutput">U<sub>x</sub></code> matches
            <code class="computeroutput">V</code> for each <code class="computeroutput">x</code> in <code class="computeroutput">[0,m]</code>.
          </p>
<p>For example:</p>
<p>
            </p>
<pre class="programlisting"><span class="comment">// Match any function call expression, regardless</span>
<span class="comment">// of the number of function arguments:</span>
<span class="keyword">struct</span> <span class="identifier">Function</span> <span class="special">:</span>
  <a class="link" href="function.html" title="Struct template function">proto::function</a><span class="special">&lt;</span> <span class="identifier">proto</span><span class="special">::</span><span class="identifier">vararg</span><span class="special">&lt;</span><span class="identifier">proto</span><span class="special">::</span><span class="identifier">_</span><span class="special">&gt;</span> <span class="special">&gt;</span>
<span class="special">{</span><span class="special">}</span><span class="special">;</span></pre>
<p>
          </p>
<p>
            When used as a transform, <code class="computeroutput">proto::vararg&lt;G&gt;</code>
            applies <code class="computeroutput">G</code>'s transform.
          </p>
</div>
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<div class="copyright-footer">Copyright © 2008 Eric Niebler<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
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